Interactive input systems that allow users to inject input such as for example digital ink, mouse events etc. into an application program using an active pointer (e.g. a pointer that emits light, sound or other signal), a passive pointer (e.g. a finger, cylinder or other object) or other suitable input device such as for example, a mouse or trackball, are well known. These interactive input systems include but are not limited to: touch systems comprising touch panels employing analog resistive or machine vision technology to register pointer input such as those disclosed in U.S. Pat. Nos. 5,448,263; 6,141,000; 6,337,681; 6,747,636; 6,803,906; 7,232,986; 7,236,162; and 7,274,356 and in U.S. Patent Application Publication No. 2004/0179001, all assigned to SMART Technologies ULC of Calgary, Alberta, Canada, assignee of the subject application, the entire contents of which are incorporated herein by reference; touch systems comprising touch panels employing electromagnetic, capacitive, acoustic or other technologies to register pointer input; tablet personal computers (PCs); laptop PCs; personal digital assistants (PDAs) and other handheld devices; and other similar devices.
Above-incorporated U.S. Pat. No. 6,803,906 to Morrison et al. discloses a touch system that employs machine vision to detect pointer interaction with a touch surface on which a computer-generated image is presented. A rectangular bezel or frame surrounds the touch surface and supports digital cameras at its four corners. The digital cameras have overlapping fields of view that encompass and look generally across the touch surface. The digital cameras acquire images looking across the touch surface from different vantages and generate image data. Image data acquired by the digital cameras is processed by on-board digital signal processors to determine if a pointer exists in the captured image data. When it is determined that a pointer exists in the captured image data, the digital signal processors convey pointer characteristic data to a master controller, which in turn processes the pointer characteristic data to determine the location of the pointer in (x,y) coordinates relative to the touch surface using triangulation. The pointer coordinates are then conveyed to a computer executing one or more application programs. The computer uses the pointer coordinates to update the computer-generated image that is presented on the touch surface. Pointer contacts on the touch surface can therefore be recorded as writing or drawing or used to control execution of application programs executed by the computer.
Such interactive input systems have typically made use of two-dimensional display surfaces. For example, in the case of the touch system described in above-incorporated U.S. Pat. No. 6,803,906 to Morrison et al., the bezel is configured to surround a flat panel display device such as a liquid crystal display (LCD) panel or plasma display panel. More recently, display systems for generating three-dimensional images have been considered. For example, U.S. Pat. No. 7,293,881 to Kasahara discloses a video projector that projects an image without reducing the resolution, onto a full dome surface. The video projector has a single-eye fisheye lens for projecting combined beams of light from a plurality of image display devices onto the dome surface.
U.S. Pat. No. 7,352,340 to Utt et al. discloses a display system comprising a display surface having a 3D convex shape. A projection unit projects images onto the display surface. The projection unit has a lens system with a convex shape that is designed to match the convex shape of the display surface such that an image can be displayed on the 3D display surface.
Display technology for displaying 3D images that makes use of holography has also been considered. OPTI-GONE International, Inc. of Ojai, Calif. has developed a holographic display offered under the name Mirage™ Model 22 Gigantic 3D Hologram Maker (http://www.optigone.com/m22.htm). FIG. 1 shows a schematic view of the Mirage™ 3D Hologram Maker 20. As can be seen, the 3D Hologram Maker 20 comprises a pair of opposing parabolic mirrors 22 and 24 that define an enclosed space 26 therebetween. An opening 28 is provided in parabolic mirror 24 at its concave center. When an object A is placed at the concave center of parabolic mirror 22, a holographic image A′ of object A that appears as a solid object projects through the opening 28.
U.S. Patent Application Publication No. 2010/0023895 to Benko et al. discloses a 3D interactive system comprising a curved display that is monitored to detect touch input on an object. FIG. 2 shows a schematic view of the Benko et al. 3D interactive system 30. As can be seen, the 3D interactive system 30 comprises a projector 32 projecting images through a wide-angle (fisheye) lens 34, into a diffuse ball 36. The 3D interactive system 30 also includes sensing components comprising an illumination ring 38 made of infrared (IR) light emitting diodes (LEDs) positioned at the bottom of diffuse ball 36, a cold mirror 40 positioned below the wide-angle lens 34, an IR pass filter 42 and an IR camera 44. An IR cut filter (not-shown) is positioned on the projector 32. Interactions on diffuse ball 36 are observed by the IR camera 44, and the projected images are updated accordingly.
Although 3D interactive input systems have been considered, improvements are sought. It is therefore an object of the present invention to provide a novel 3D interactive input system and method.